I'm thinking about trying something new in RtL to addess the balance issues:

What if the Overlord deck was scaled with the campaign level?

These forums indicate most people think that the game is too difficult for the heroes in the copper level, and too easy for them in the gold. What if the overlord only draws one card per turn in copper, and three in gold?

There might be other adjustments needed for the hand size, threat gains, and the like too. I haven't tried it yet, this is just a thought exercise currently.

thoughts?

I think adjustments to Threat gain could go a long way.

I think this is a fantastic idea. Maybe something like 3 threat per turn instead of 4 at copper. 5 a turn at Gold.

Maybe hand size limit to 6 at copper, 10 at gold.

All good ideas. Other peoples opinions welcome as I'm starting a new campaign in 2 days time.